Response function and kinetic coefficients of chaotic systems

Abstract

Abstract.Stochastic approach based on the semiclassical approximation is developed for the description of finite Fermi-systems dynamics. The response function in the quadrupole external field is calculated in the framework of the independent particle model for the harmonic oscillator and square-well average potentials. Considerable excess of the smooth term of the cranking-model inertial coefficient over the hydrodynamics value is demonstrated. Connection between the friction coefficient and onebody relaxation time is obtained.

Stochastic aspects of nuclear large amplitude motion

“…The value of the mass parameter Bo in (5.7) is significantly larger than that obtained in the irrotational hydrodynamic model, Bhang" in Ref. [6]. This excess can be explained as the vortex motion contribution to Bp.…”

“…The variance 0 can be calculated from classical quantities in systems which have a chaotic classical limit [3,6] n In accordance with Sec. III we fulfill the time smearing of E2 (4.7) as…”

“…Assuming that the matrix elements (g~( 9H/Bq~Q ) are independently Gaussian distributed, it was shown [3] that P(e) = W-(E) 6 (for small e), (s.s) P'(g) = exp{ -)q /8o. ).…”

“…The additional contribution Bs", t, (E) to the partial mass coefficient (5.7) depends on the excitation energy E of the nucleus and is given by The calculation of the collective mass Bp depends on the classical correlation function C~(r) in (3.12), which was investigated in a simple independent particle model [6]. In the case of an axially symmetric.…”

“…The classical correlation function (3.12) and the corresponding response function (5.4), mass coefricient (5.6), dissipation energy (6.6) and (6.7), and difFusion coefficient (3.16) have been calculated for the axially symmetric harmonic oscillator in Ref. [6]. In the case of the high excitation energy regime, where the initial excitation energy is E, ;"=20 MeV and the initial collective kinetic energy is Ep;";"--1 MeV, the scission time v";"is sensitive to the spectral statistics.…”